The fabled days of MGM at the crest of its manufacturing of musicals, very amusingly re-created by a top arranger-conductor. Sixteen-year-old musical whiz Previn started work in MGM's music department in 1948--and stuck around until 1964. A German refugee who had attended the Paris Conservatory and was a phenomenal sight reader, Previn had endured a stint as an improvising pianist for a silent-movie revival house and been arranging for radio shows when MGM's music department hired him to write some jazz variations on ""Three Blind Mice."" More minor jobs at MGM had landed him, by 18, a contract as a staff arranger and his first solo credit on the screen, for The Sun Comes Up, based on a novel by Marjorie Kinnan Rawlings. Moat of his early work, he says here, was on nonsensical, forgotten films that still embarrass him when he catches them on late-night TV. But his education bounded forward, and before he left he'd won Oscars for Gigi, Porgy and Bess, My Fair Lady, and Irma la Douce. His story here is told anecdotally around such figures as Jascha Heifetz, the great film composers Erich Wolfgang Korngold, Miklos Rozsa, Bernard Herrmann, and William Walton, directors Vincente Minelli, George Cukor, young Mike Nichols, and Billy Wilder, studio heads L.B. Mayer, Jack Warner, and Sam Goldwyn, and actors Rex Harrison, Ava Gardner, Fred Astaire--and Lassie. Previn had the rankling privilege of being snubbed by Lassie, which he attributed to his low caste as a musician. At times, his stories bring outright laughter, such as his being discovered with pianist Mel Powell playing four-hand Haydn symphonies on an old upright piano outdoors in a snowstorm. Sheer charm.